Soprano::LiteralValue Class Reference

Represents a literal value of an RDF Node. More...

#include <Soprano/LiteralValue>

List of all members.

Public Member Functions
	LiteralValue (const QByteArray &data)
	LiteralValue (const QDateTime &datetime)
	LiteralValue (const QTime &time)
	LiteralValue (const QDate &date)
	LiteralValue (const QString &string)
	LiteralValue (const QLatin1String &string)
	LiteralValue (const char *string)
	LiteralValue (double d)
	LiteralValue (bool b)
	LiteralValue (qulonglong i)
	LiteralValue (uint i)
	LiteralValue (qlonglong i)
	LiteralValue (int i)
	LiteralValue (const QVariant &v)
	LiteralValue (const LiteralValue &other)
	LiteralValue ()
	~LiteralValue ()
QUrl	dataTypeUri () const
bool	isBool () const
bool	isByteArray () const
bool	isDate () const
bool	isDateTime () const
bool	isDouble () const
bool	isInt () const
bool	isInt64 () const
bool	isPlain () const
bool	isString () const
bool	isTime () const
bool	isUnsignedInt () const
bool	isUnsignedInt64 () const
bool	isValid () const
LanguageTag	language () const
bool	operator!= (const LiteralValue &other) const
LiteralValue &	operator= (const QByteArray &data)
LiteralValue &	operator= (const QDateTime &datetime)
LiteralValue &	operator= (const QTime &time)
LiteralValue &	operator= (const QDate &date)
LiteralValue &	operator= (const QLatin1String &s)
LiteralValue &	operator= (const QString &s)
LiteralValue &	operator= (double d)
LiteralValue &	operator= (bool b)
LiteralValue &	operator= (qulonglong i)
LiteralValue &	operator= (uint i)
LiteralValue &	operator= (qlonglong i)
LiteralValue &	operator= (int i)
LiteralValue &	operator= (const LiteralValue &other)
bool	operator== (const LiteralValue &other) const
bool	toBool () const
QByteArray	toByteArray () const
QDate	toDate () const
QDateTime	toDateTime () const
double	toDouble () const
int	toInt () const
qlonglong	toInt64 () const
QString	toString () const
QTime	toTime () const
uint	toUnsignedInt () const
qulonglong	toUnsignedInt64 () const
QVariant::Type	type () const
QVariant	variant () const
Static Public Member Functions
static LiteralValue	createPlainLiteral (const QString &value, const LanguageTag &lang=LanguageTag())
static QUrl	dataTypeUriFromType (QVariant::Type type)
static LiteralValue	fromString (const QString &value, const QUrl &dataTypeUri)
static LiteralValue	fromString (const QString &value, QVariant::Type type)
static QVariant::Type	typeFromDataTypeUri (const QUrl &dataTypeUri)

---

Detailed Description

Represents a literal value of an RDF Node.

LiteralValue is based on QVariant to support a subset of the XML Schema types that are compatible with QT types.

The following types are supported natively including automatic type conversion. Other types are represented as strings.

• int (Vocabulary::XMLSchema::xsdInt)
• qlonglong (Vocabulary::XMLSchema::xsdLong)
• unsigned int (Vocabulary::XMLSchema::unsignedInt)
• qulonglong (Vocabulary::XMLSchema::unsignedLong)
• bool (Vocabulary::XMLSchema::boolean)
• double and float (Vocabulary::XMLSchema::xsdDouble) (float values are always converted to double)
• QString (Vocabulary::XMLSchema::string or Vocabulary::RDF::XMLLiteral)
• QDate (Vocabulary::XMLSchema::date)
• QTime (Vocabulary::XMLSchema::time)
• QDateTime (Vocabulary::XMLSchema::dateTime)
• QByteArray (Vocabulary::XMLSchema::base64Binary)

Literal values can be converted from strings via fromString().

See also:

Vocabulary::XMLSchema

Author:

Sebastian Trueg <trueg@kde.org>

Definition at line 66 of file literalvalue.h.

---

Constructor & Destructor Documentation

Soprano::LiteralValue::LiteralValue

(

)

Create an empty literal value.

Soprano::LiteralValue::~LiteralValue

(

)

Destructor.

Soprano::LiteralValue::LiteralValue

(

const LiteralValue &

other

)

Default copy constructor.

Soprano::LiteralValue::LiteralValue

(

const QVariant &

v

)

Creates a new LiteralValue from a QVariant.

User types are not supported. If v contains an unsupported type an invalid LiteralValue is created.

Soprano::LiteralValue::LiteralValue

(

int

i

)

Creates a literal value of type int (i.e.

http://www.w3.org/2001/XMLSchema#int)

Soprano::LiteralValue::LiteralValue

(

qlonglong

i

)

Creates a literal value of type long long (i.e.

http://www.w3.org/2001/XMLSchema#long)

Soprano::LiteralValue::LiteralValue

(

uint

i

)

Creates a literal value of type unsigned int (i.e.

http://www.w3.org/2001/XMLSchema#unsignedInt)

Soprano::LiteralValue::LiteralValue

(

qulonglong

i

)

Creates a literal value of type unsigned long long (i.e.

http://www.w3.org/2001/XMLSchema#unsignedLong)

Soprano::LiteralValue::LiteralValue

(

bool

b

)

Creates a literal value of type bool (i.e.

http://www.w3.org/2001/XMLSchema#boolean)

Soprano::LiteralValue::LiteralValue

(

double

d

)

Creates a literal value of type double (i.e.

http://www.w3.org/2001/XMLSchema#double)

Soprano::LiteralValue::LiteralValue

(

const char *

string

)

Creates a literal value of type QString (i.e.

http://www.w3.org/2001/XMLSchema#string)

Parameters:

string

The value of the new literal interpreted as UTF-8 encoded string.

Soprano::LiteralValue::LiteralValue

(

const QLatin1String &

string

)

Creates a literal value of type QString (i.e.

http://www.w3.org/2001/XMLSchema#string)

Soprano::LiteralValue::LiteralValue

(

const QString &

string

)

Creates a literal value of type QString (i.e.

http://www.w3.org/2001/XMLSchema#string)

Soprano::LiteralValue::LiteralValue

(

const QDate &

date

)

Creates a literal value of type QDate (i.e.

http://www.w3.org/2001/XMLSchema#date)

Soprano::LiteralValue::LiteralValue

(

const QTime &

time

)

Creates a literal value of type QTime (i.e.

http://www.w3.org/2001/XMLSchema#time)

Soprano::LiteralValue::LiteralValue

(

const QDateTime &

datetime

)

Creates a literal value of type QDateTime (i.e.

http://www.w3.org/2001/XMLSchema#dateTime)

Soprano::LiteralValue::LiteralValue

(

const QByteArray &

data

)

Creates a literal value of type QByteArray (i.e.

http://www.w3.org/2001/XMLSchema#base64Binary)

---

Member Function Documentation

static LiteralValue Soprano::LiteralValue::createPlainLiteral	(	const QString &	value,
		const LanguageTag &	lang = LanguageTag()
	)			[static]

Create a plain LiteralValue object with an optional language tag.

Parameters:

	value	The value of the literal.
	lang	The language tag.

Both an empty value and lang will result in an invalid LiteralValue instance but an empty value with a valid lang is possible. A valid value with an empty lang will result in a plain, untyped literal with no language tag.

Returns:

A newly created LiteralValue instance based on the provided value and lang.

QUrl Soprano::LiteralValue::dataTypeUri

(

)

const

The XML Schema datatype URI.

Returns:

The URI of the XML Schema type referring to the stored type or an empty QUrl if the LiteralValue is empty or is a plain literal.

static QUrl Soprano::LiteralValue::dataTypeUriFromType

(

QVariant::Type

type

)

[static]

Convert a QVariant::Type into an XML Schema URI.

Returns:

The XML Schema URI that corresponds to type or an empty QUrl if the type os unknown, i.e. can not be mapped to an XML Schema type.

static LiteralValue Soprano::LiteralValue::fromString	(	const QString &	value,
		const QUrl &	dataTypeUri
	)			[static]

Create a LiteralValue object by parsing string value based on dataTypeUri.

Parameters:

	value	The value of the literal. Might be converted based on dataTypeUri.
	dataTypeUri	The data type URI. Soprano can automatically convert all XML schema types. All other (unknown) types will be stored as a string value with the plain dataTypeUri as type. Thus, unknown literal types can still be used without automatic type conversion. (Be aware though, that changing the value of a LiteralValue instance will reset the type, ie. custom data type URIs will be lost.)

Both an empty value and dataTypeUri will result in an invalid LiteralValue instance but an empty value with a valid dataTypeUri is possible. A valid value with an invalid dataTypeUri will result in a LiteralValue of type Vocabulary::XMLSchema::string.

Returns:

A newly created LiteralValue instance based on the provided value and dataTypeUri.

See also:

fromString(const QString&, QVariant::Type), Vocabulary::XMLSchema

static LiteralValue Soprano::LiteralValue::fromString	(	const QString &	value,
		QVariant::Type	type
	)			[static]

Create a LiteralValue object by parsing string value based on type.

If type is unknown a simple string LiteralValue object is returned containing the plain string value.

See also:

fromString(const QString&, const QUrl&)

bool Soprano::LiteralValue::isBool

(

)

const

bool Soprano::LiteralValue::isByteArray

(

)

const

bool Soprano::LiteralValue::isDate

(

)

const

bool Soprano::LiteralValue::isDateTime

(

)

const

bool Soprano::LiteralValue::isDouble

(

)

const

bool Soprano::LiteralValue::isInt

(

)

const

bool Soprano::LiteralValue::isInt64

(

)

const

bool Soprano::LiteralValue::isPlain

(

)

const

Determines if this literal value is a plain literal.

Plain literals have no data type, but may have an optional language tag.

Returns:

true if this literal is plain

bool Soprano::LiteralValue::isString

(

)

const

Check if the literal contains a string value.

Be aware that unknown literal types are also treated as strings. In that case compare dataTypeUrl.

bool Soprano::LiteralValue::isTime

(

)

const

bool Soprano::LiteralValue::isUnsignedInt

(

)

const

bool Soprano::LiteralValue::isUnsignedInt64

(

)

const

bool Soprano::LiteralValue::isValid

(

)

const

LanguageTag Soprano::LiteralValue::language

(

)

const

The language tag.

Returns:

The language tag of the plain literal or an empty LanguageTag if the LiteralValue has no language or it is a typed literal.

bool Soprano::LiteralValue::operator!=

(

const LiteralValue &

other

)

const

LiteralValue& Soprano::LiteralValue::operator=

(

const QByteArray &

data

)

Assigns datetime to this literal value.

The type will be set to ByteArray (http://www.w3.org/2001/XMLSchema#base64Binary).

LiteralValue& Soprano::LiteralValue::operator=

(

const QDateTime &

datetime

)

Assigns datetime to this literal value.

The type will be set to dateTime (http://www.w3.org/2001/XMLSchema#dateTime).

LiteralValue& Soprano::LiteralValue::operator=

(

const QTime &

time

)

Assigns time to this literal value.

The type will be set to time (http://www.w3.org/2001/XMLSchema#time).

LiteralValue& Soprano::LiteralValue::operator=

(

const QDate &

date

)

Assigns date to this literal value.

The type will be set to data (http://www.w3.org/2001/XMLSchema#date).

LiteralValue& Soprano::LiteralValue::operator=

(

const QLatin1String &

s

)

Assigns s to this literal value.

The type will be set to string (http://www.w3.org/2001/XMLSchema#string).

LiteralValue& Soprano::LiteralValue::operator=

(

const QString &

s

)

Assigns s to this literal value.

The type will be set to string (http://www.w3.org/2001/XMLSchema#string).

LiteralValue& Soprano::LiteralValue::operator=

(

double

d

)

Assigns d to this literal value.

The type will be set to double (http://www.w3.org/2001/XMLSchema#double).

LiteralValue& Soprano::LiteralValue::operator=

(

bool

b

)

Assigns b to this literal value.

The type will be set to bool (http://www.w3.org/2001/XMLSchema#boolean).

LiteralValue& Soprano::LiteralValue::operator=

(

qulonglong

i

)

Assigns i to this literal value.

The type will be set to unsigned long (http://www.w3.org/2001/XMLSchema#unsignedLong).

LiteralValue& Soprano::LiteralValue::operator=

(

uint

i

)

Assigns i to this literal value.

The type will be set to uint (http://www.w3.org/2001/XMLSchema#unsignedInt) unless it is already set to a compatible type.

Thus, a type http://www.w3.org/2001/XMLSchema#unsignedShort will not be changed.

Be aware that Soprano does not check the ranges of the unsigned value yet.

LiteralValue& Soprano::LiteralValue::operator=

(

qlonglong

i

)

Assigns i to this literal value.

The type will be set to long (http://www.w3.org/2001/XMLSchema#long).

LiteralValue& Soprano::LiteralValue::operator=

(

int

i

)

Assigns i to this literal value.

The type will be set to int (http://www.w3.org/2001/XMLSchema#int) unless it is already set to a compatible type.

Thus, a type http://www.w3.org/2001/XMLSchema#integer or http://www.w3.org/2001/XMLSchema#decimal will not be changed.

Be aware that Soprano does not check the ranges of the integer value yet.

LiteralValue& Soprano::LiteralValue::operator=

(

const LiteralValue &

other

)

Creates a copy of other.

bool Soprano::LiteralValue::operator==

(

const LiteralValue &

other

)

const

bool Soprano::LiteralValue::toBool

(

)

const

QByteArray Soprano::LiteralValue::toByteArray

(

)

const

QDate Soprano::LiteralValue::toDate

(

)

const

QDateTime Soprano::LiteralValue::toDateTime

(

)

const

double Soprano::LiteralValue::toDouble

(

)

const

int Soprano::LiteralValue::toInt

(

)

const

qlonglong Soprano::LiteralValue::toInt64

(

)

const

QString Soprano::LiteralValue::toString

(

)

const

Each type can be converted to a string which means that toString in combination with dataTypeUrl provides all the information necessary to store this literal as RDF.

The string value is cached so calling it multiple times in a row is fast.

Warning:

For historical reasons this is not a user-readable representation.

See also:

Node::toString

QTime Soprano::LiteralValue::toTime

(

)

const

uint Soprano::LiteralValue::toUnsignedInt

(

)

const

qulonglong Soprano::LiteralValue::toUnsignedInt64

(

)

const

QVariant::Type Soprano::LiteralValue::type

(

)

const

The type of the data.

Returns:

The QVariant type of the stored data or QVariant::Invalid if it is an empty value.

static QVariant::Type Soprano::LiteralValue::typeFromDataTypeUri

(

const QUrl &

dataTypeUri

)

[static]

Convert an XML Schema URI into a QVariant::Type.

Returns:

The QVariant::Type corresponding to dataTypeUri or QVariant::Invalid if dataTypeUri is unknown.

QVariant Soprano::LiteralValue::variant

(

)

const

The literal value represented in a QVariant.

Be aware that the RDF typing information is lost in the converted variant.

---

The documentation for this class was generated from the following file:

• literalvalue.h